Field of the Invention
The present disclosure is related to a three-dimensional printing apparatus, and more particularly to a Stereolithography (SL) three-dimensional printing apparatus.
Description of Related Art
In recent years, with the increasing development of technology, various methods for building three-dimensional (3D) models with the use of additive manufacturing technology such as a layer-by-layer structuring model are provided one after another. In general, the additive manufacturing technology transforms design information of the 3D models structured by softwares such as computer-aided design (CAD) into a plurality of thin (quasi-two-dimensional) cross-section layers that are stacked continuously. Meanwhile, many technical means capable of forming a plurality of thin cross-section layers are gradually provided. For instance, a printing module of a printing apparatus usually moves above a base along an XY plane according to space coordinates XYZ structured by the design information of the 3D model, so that structuring materials are formed into correct shapes of the cross-section layers. Deposited structuring materials subsequently harden naturally or are solidified through heating or irradiation by a light source, and thereby a desired cross-section layer is formed. Therefore, by means of the movement of the printing module along an axis Z layer by layer, the plurality of cross-section layers are gradually stacked along a Z-axis, so that the structuring material forms the 3D object in a status of solidification layer by layer.
Take the Stereolithography (SL) 3D printing apparatus that forms the 3D object by solidifying the structuring materials through the light source, the printing module is adapted for immersion in a liquid-forming material contained in a tank, and a light source module irradiates the liquid-forming material serving as the structuring material on the XY plane, so that the liquid-forming material is solidified and stacked on a movable platform of the printing module. Thereby, by means of the movement of the movable platform of the printing module along the axis Z layer by layer, the liquid-forming material is solidified layer by layer and stacked to form the 3D object. However, the process that the 3D object is formed by layer-by-layer stacking keeps consuming the liquid-forming material in the tank, and currently it still requires constant attention by operating staff alongside to keep an eye on the remaining amount of the liquid-forming material in the tank and manually replenish the tank with the liquid-forming material from time to time. Therefore, operation of the current SL 3D printing apparatus is still very much inconvenient. Furthermore, if the liquid-forming material of the SL 3D printing apparatus is exhausted during the printing process due to momentary oversight by the operating staff, printing fails. In addition, since it is relatively difficult to control the amount of replenishment, when the operating staff replenishes the tank with the liquid-forming material, it often occurs that the liquid-forming material spills over due to excessive replenishment, which thereby causes damages to the apparatus. Therefore, it gradually becomes the focus of attention by developers in the art to effectively reduce the operating and maintenance costs of the 3D printing apparatus.